Configuration of dislocations in low-angle kink boundaries formed in a single crystalline long-period stacking ordered Mg-Zn-Y alloy
Configuration of dislocations in low-angle kink boundaries formed in a single crystalline long-period stacking ordered Mg-Zn-Y alloy
复制标题
DOI：
10.1016/j.actamat.2018.03.034
复制
发表时间：
2018-06
期刊：
影响因子：
9.4
通讯作者：
Tsubasa Matsumoto;M. Yamasaki;K. Hagihara;Y. Kawamura
中科院分区：
文献类型：
--
作者：
Tsubasa Matsumoto;M. Yamasaki;K. Hagihara;Y. Kawamura
研究了单晶长周期堆垛有序（LPSO）Mg 85 Zn 6 Y 9合金弯曲时小角度扭折晶界附近的位错组态。通过SEM/EBSD观察进行晶内取向差轴（IGMA）分析和通过TEM观察进行g· B分析。通过IGMA分析，发现了具有不同晶格旋转轴的扭折带，其旋转轴从< 1 1 <$00>到< 1 2 <$10>，即沿着< 1 1 <$00>、< uvt0>、和< 1 2 <$10>。TEM观察和g· B分析表明，IGMA分析发现< 1 1 00>-旋转扭折边界由< a>具有一个Burgers矢量的基底刃位错组成，而< 1 2 10>/< uvt0>-旋转扭折边界由< a>具有多个Burgers矢量的基底刃位错组成。低角扭折边界被认为是由完全基底位错组成的低角倾斜边界< a>，而与它们的旋转轴无关。不同< uvt0>组合旋转轴在< 1 1 <$00>~< 1 2 <$10>范围内的扭折带的形成表明，在小角度扭折边界形成的初始阶段，统计存储的基底< a>位错可能转变为几何上必需的基底< a>刃位错。当一个扭结边界被认为是一个向错，IGMA分析能够确定晶格旋转轴和角度是有效的，在评估的弗兰克矢量的扭结边界。
The dislocation configuration around low-angle kink boundaries formed in bent single crystalline long-period stacking ordered (LPSO) Mg 85 Zn 6 Y 9 alloys was investigated. Intragranular misorientation axis (IGMA) analysis through SEM/EBSD observation and g• b analysis through TEM observation were conducted. Various kink bands possessing different lattice rotation axes ranging from< 1 1¯ 00> to< 1 2¯ 10>, ie along< 1 1¯ 00>,< uvt0>, and< 1 2¯ 10> were revealed using IGMA analysis. TEM observation with g• b analysis unveiled that the< 1 1¯ 00>-rotation kink boundary observed using IGMA analysis consisted of basal< a> edge dislocations with one Burgers vector, while the< 1 2¯ 10>/< uvt0>-rotation kink boundaries were comprised of basal< a> edge dislocations with more than one Burgers vector. Low-angle kink boundaries were regarded as low-angle tilt boundaries consisting of perfect basal< a> dislocations, regardless of their rotation axes. The formation of various kink bands with< uvt0>-combination-rotation axes ranging from< 1 1¯ 00> to< 1 2¯ 10> suggests that the statistically stored basal< a> dislocations may turn into geometrically necessary basal< a> edge dislocations during the initial stage of low-angle kink boundary formation. When a kink boundary is considered as a disclination, IGMA analysis capable of determining the lattice rotation axis and the angle is effective in evaluating the Frank vector of the kink boundary.